1. Field of the Invention
The present invention relates to an absorbent composite sheet having small thickness and providing good skin contacting feeling, and an absorbent article using the same.
2. Description of the Related Art
It is a typical structure of the conventional absorbent article, such as sanitary napkin, panty liner for absorbing lady's virginal discharge or the like, to provide a liquid absorbing layer below a liquid permeable top sheet, and a liquid blocking back sheet stacked below the liquid absorbing layer. However, since the top sheet, the liquid absorbing layer and the back sheet are formed independently of each other and the absorbent article is formed by simply stacking these components, there is inherent limitation for making the absorbent article thinner. On the other hand, during manufacturing process of the absorbent article, it is required a process step of stacking the top sheet, the liquid absorbing layer and the back sheet to necessitate extra manufacturing step to restrict reduction of cost.
On the other hand, the conventional absorbent composite sheet capable of absorbing liquid by stacking or laminating the sheets has been proposed in Japanese Unexamined Patent Publication No. Heisei 7(1995)-155595.
Such conventional absorbent composite sheet is a composite body having a first layer formed by entangling cellulose type fibers (or cellulosic fibers) to a net form core body fabricated from hydrophobic fibers and a second layer formed by entangling cellulose type fibers to a net form core body fabricated from hydrophobic fibers and calboxymethylation and cross-linking of cellulose type fibers for binding to form superabsorbent polymer sheet. The net form core bodies of the first and second layers are fuse bonded for binding the first and second layers for forming the composite body.
The absorbent composite sheet has cellulose type fibers in both of the first and second layers for providing liquid absorbing and holding capacity in both of the first and second layers. Also, by forming the second layer as superabsorbent polymer sheet, higher absorbing capacity than the first layer is provided for easily transferring liquid from the first layer to the second layer and for easily absorbing the liquid in the first layer.
However, since the absorbent composite sheet disclosed in the above-identified publication has the first layer mainly formed from hydrophilic cellulose type fibers, the first layer is situated in a condition constantly containing the liquid. Also, since both of the first layer and the second layer have liquid absorbing capacity, it is inevitable that the liquid absorbed by the second layer is wetted back to the first layer. As disclosed in the above-identified publication, the absorbent composite sheet can be used as absorbent body of the sanitary napkin or the like. However, it is difficult to take a structure to directly contact the first layer to wearer's skin.
If the first layer is placed in direct contact with the wearer's skin, the liquid remained in the first layer and the liquid wetted back from the second layer to the first layer may possibly provide wet feeling to the skin and can cause skin fit on the skin in direct contact with the first layer.